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Teen Girls' Health

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All About Menstruation

Ever wonder what really happens during menstruation, when a girl enters puberty and has her period? Maybe you’ve wanted to talk to your mom, sister, or dad about it. But each time you said the word "menstruation," you stuttered, stammered, and could barely pronounce it.

It’s OK. Everyone is timid when talking about bodily functions, especially one as mysterious as the menstrual period. Perhaps this article can answer some of your questions about this normal time in every girl's life.

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What Is Menstruation?

Shortly after the beginning of puberty in girls, and usually about 2 years after the development of breasts, menstruation starts. While menstruation usually begins between ages 12 and 13, it may happen at a younger or older age. The first menstrual period is called "menarche."

The menstrual cycle is about four weeks long, starting on the first day of bleeding and ending when the next period begins. However, it can vary greatly when a girl first starts her period. It may skip months or come several times per month in the beginning.

The menstrual discharge comes from the uterus through the vagina. The uterus is a hollow, pear-shaped organ, responsible for maintaining and nourishing the embryo and fetus during a pregnancy. The vagina, or "birth canal," provides a path for menstrual fluids to leave the body.

During a period, there are usually 2-3 days of relatively heavy bleeding followed by 2-4 days of lighter flow. The fluid during a menstrual period is a mixture of uterine lining tissue and blood.

The total monthly menstrual loss varies from about 4 to 12 teaspoons.

What Does a Menstrual Period Feel Like?

A few days before and during your period, you might feel cramping and bloating in your abdomen. The cramps are caused by increased production of hormones. These hormones (called prostaglandins) cause the muscles of the uterus to contract.

Many teens who have cramps also notice aching in the upper thighs along with lower back pain. Some also notice nausea, diarrhea, irritability, headaches, and fatigue, among other symptoms.

To ease cramping, try applying heat to your abdomen with a heating pad or hot water bottle. Taking a warm bath may also help. Some teens find that exercise helps relieve cramps. Exercise improves blood flow and produces endorphins, the body’s natural painkillers.

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